Key Terms
Macronutrients
H, C, O, N, P, S — account for ~99% of dry cell weight. Most abundant element in cells: hydrogen.
Micronutrients (trace elements)
Na, K, Mg, Zn, Fe, Ca, Mo, Cu, Co, Mn, V. Required in very small amounts; still essential to biochemical function.
Organic molecules
Contain carbon; atoms organized around carbon chains.
Inorganic compounds
Do not contain carbon (with exceptions below).
Exceptions
Carbon oxides (CO2) and carbonates contain carbon but are classified as inorganic because they lack hydrogen.
Isomers
Same atomic makeup, different structural arrangement.
Structural isomers
Same molecular formula, different bonding sequence.
Example
Lancefield group tests for Streptococcus species identification.
Stereoisomers
Same bonding sequence, different spatial arrangement of atoms. Enantiomers: a unique type of stereoisomer.
Discovered by
Louis Pasteur in 1848, analyzing crystallized fermentation products from wine under a microscope. Observed that some cry
Also called
Optical isomers (because they rotate polarized light).
Functional groups
Specific clusters of atoms within molecules; defined by chemical composition and reactions they perform. R in structural
Macromolecules
Large biomolecules built from smaller building blocks.
Monomers
The small repeating building block units. Polymers: macromolecules formed by linking monomers.
Dehydration synthesis
Reaction linking monomers by removing water; produces polymers. Denaturation: loss of secondary/tertiary/quaternary stru